DESCRIPTION: (Adapted from the Application) Rationale: Poor adherence to prescribed treatments leads to poor outcomes in persons with chronic disease. It is a major contributor to the very high rates of cardiovascular disability and death observed among type 2 diabetic patients. The goal is to reduce the incidence and severity of cardiovascular disease among high-risk patients treated in primary care settings by improving their adherence to prescribed treatments. The aims are as follows. 1) Test the effectiveness of an original and practical intervention designed to foster the involvement of a relative or friend in cardiovascular risk reduction for patients with type 2 diabetes, focusing on using this type of social support to improve adherence to prescribed treatments. Primary outcomes of interest (12 months of follow-up): blood pressure levels, serum lipids levels, health-related quality of life, cost effectiveness, patient satisfaction, and glaciated hemoglobin levels. 2) Investigate the intervention?s theorized cognitive-behavioral mechanisms of action: adherence to treatment, patients? health beliefs (including self-efficacy and locus of control), and support person involvement. Setting: Fifteen community-based primary care practices in a practice-based research network. Subjects: 375 patients with type 2 diabetes plus suboptimally-controlled hypertension and/or dyslipidemia, who express willingness to formally involve a relative or friend as a support person (SP) in their medical care. Protocol: Subjects will be randomized (at the physician level) with equal chances to the Control Group, Intervention Group A or Intervention Group B. All subjects will complete one brief patient education session and receive quarterly newsletters (control condition). Those in the Intervention Groups will bring their SP to the education session, and the SP will also get special newsletters. The specified outcomes in Intervention Group A will be compared with those in the Control Group to test hypotheses of effectiveness. To mitigate potential Hawthorne Effects, only patients and SPs in Intervention Group B will undergo the intense scrutiny needed to investigate the theorized cognitive-behavioral mechanisms behind the intervention.